Abstract
Selective oxidation of alcohols is an attractive organic transformation and has received tremendous attention from the scientific community over the years. Herein, a mesoporous polymer (MP) was synthesized by a template-free solvothermal approach. The surface of the MP was functionalized with quaternary ammonium groups and polyoxotungstate anion (PW(11)O(39) (7-)) was subsequently supported on the MP as a counter anion to the ammonium cation by a simple ion-exchange procedure. The structure of PW(11) and PW(4) complexes was confirmed by (31)P NMR and FTIR analysis. The surface properties of all the catalysts synthesized were explored by various characterization techniques such as nitrogen sorption, TGA, contact angle measurement, and ICP-OES analysis. The synthesized PW(11)/MP catalysts were employed for selective oxidation of alcohols. Among the various PW(11) supported catalysts, PW(11)/MP (80 : 20) demonstrated excellent catalytic activity for the oxidation of alcohols using aqueous H(2)O(2). The PW(11)/MP (80 : 20) catalyst showed good catalytic activity for oxidation of a wide range of alcohols including substituted, heterocyclic and secondary alcohols. The superior catalytic activity of PW(11)/MP (80 : 20) is attributed to an optimum balance in the hydrophilicity/hydrophobicity in the mesoporous environment, better catalyst wettability, and enrichment of reactants in the catalytic active sites.